text: PDRCs can also come in the form of metafabrics, which can be worn as clothing to shield and regulate body temperatures in times of extreme heat. Most metafabrics are made of petrol-based fibers, although research and development of sustainable or regenerative materials is ongoing. For instance, Zhong et al. states that "new flexible cellulose fibrous films with wood-like hierarchical microstructures need to be developed for wearable PDRC applications."
  By Shaoning Zeng et al they choose a material chosen, a composite of titanium oxide and polylactic acid (TiO2-PLA) with a polytetrafluoroethylene (PTFE) lamination, was pivotal in achieving the desired optical characteristics. The fabric underwent thorough optical and thermal characterization, measuring essential properties like reflectivity and emissivity. Numerical simulations, including Lorenz-Mie theory and Monte Carlo simulations, were crucial in predicting the fabrics performance and guiding its optimization. Additionally, mechanical testing was conducted to ensure the fabrics durability, strength, and practicality for everyday use.
  One of the most notable results was the metafabrics exceptional ability to facilitate radiative cooling. The fabric achieved high emissivity (94.5%) in the atmospheric window, which is crucial for radiative cooling as it allows body heat to be effectively radiated away. Simultaneously, it exhibited high solar reflectivity (92.4%), meaning it could reflect a significant portion of the suns rays, further contributing to its cooling effect. This combination of high emissivity and reflectivity is central to its cooling capabilities, significantly outperforming traditional fabrics in this regard. Additionally, the fabric's mechanical properties, including strength, durability, waterproofness, and breathability, confirmed its suitability for everyday clothing. This combination of high radiative cooling performance and strong mechanical properties makes the fabric a promising candidate for practical applications.
  * Liu et al. (2022), eco-friendly bio-derived regenerable polymer alginate to modify cotton fiber and then in-matrix generate Calcium carbonate| nano- or other micro-particles, solar reflectance 90%, heat emittance 97%, lowered human skin temperature by 5.4ᵒC, "fully compatible with industrial processing facilities" and with "effective UV protection properties with a UPF value of 15, is fast-dry, and is stable against washing."
  * Li et al. (2022), wearable hat constructed of a radiative cooling paper with Silicon dioxide| fibers and fumed , solar reflectance 97%, heat emittance 91%, reduced temperatures for the hair of the wearer by 12.9ᵒC when compared with a basic white cotton hat (and 19ᵒC when compared with no hat), waterproof and air permeable, "suitable for the manufacture of radiative cooling hat to achieve the thermal management of human head."